Evaluate the safety and immunogenicity of a polyvalent HIV-1 C4-V3 synthetic peptide mixture formulated in Incomplete Freund's Adjuvant (IFA, mineral oil containing mannose mono-oleate). Four synthetic peptides based on the HIV-1 clade B strains MN, EV91, RF, and CANO are included in the candidate vaccine. Each of these four component peptides consists of two sections or parts. The first, C4 section, is a 15 amino acid sequence corresponding to a potent activator of anti-HIV memory helper T cells present in the fourth conserved region of HIV-1 gp 120 of the particular HIV-1 strain. The V3 region is an established B cell epitope recognized by anti-HIV neutralizing antibodies, as well as being an HLA-B7 restricted CTL epitope. The same C4 sequence 15 is used in all four of the pooled fusion peptides, while the V3 portion of the fusion peptide is unique for each strain. The candidate vaccine, hereafter referred to as C4-V3 peptides, is to be given by intramuscular injection to healthy, HIV-1 uninfected adult volunteers at low risk of infection w/HIV-1.